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TCR15AG065
Reference Manual
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Toshiba TCR15AG065, TCR15AG08, TCR15AG07, TCR15AG075, TCR15AG085 Reference Manual

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© 2019
RD030-RGUIDE-02
LDO Regulator TCR15AG
(fixed output voltage type)
Application & Circuit
Reference Guide
RD030-RGUIDE-02
2019-05-08
Rev.2
RD030-RGUIDE-02
2 / 18
© 2019
Table of Contents
1. OVERVIEW .............................................................................................................. 3
1.1. Target applications ............................................................................................... 4
2. APPLICATION CIRCUIT EXAMPLE AND BILL OF MATERIALS ..................................... 5
2.1. Application circuit example ................................................................................... 5
2.2. Bill of materials ..................................................................................................... 5
3. MAJOR FEATURES OF THE TCR15AG SERIES ............................................................ 6
3.1. V
3.2. Achieving a high PSRR and the influence of an output capacitor on the PSRR ........ 9
3.3. Achieving a fast high-load transient response ......................................................10
4. OUTPUT VOLTAGE ...................................................................................................12
5. DESIGN CONSIDERATIONS .....................................................................................14
6. PRODUCT OVERVIEW ..............................................................................................15
6.1. TCR15AG (fixed voltage type) ..............................................................................15
6.1.1. Overview ..............................................................................................................15
6.1.2. External view and pin assignment .......................................................................15
6.1.3. Internal block diagram ........................................................................................17
pin ................................................................................................................ 6
BIAS
6.1.4. Pin description ....................................................................................................17
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1. Overview

For the purpose of requiring low power consumption application, it is general that average power
consumption goes down balancing total system utilization and supplying power. Especially
smartphone and tablet, there is a trade-off between the size and weight of the device and their
battery capacity while a high level of power management is necessary, but in the application there
are various electronic circuits including wireless communication, camera, display, audio, and storage
circuits, so it is necessary to control their power supplies surely.
Power management ICs (PMICs) are used in smartphones, tablets, and other small battery-
operated devices to achieve accurate power management. A PMIC consists of a few to a few dozen
power supply channels of DC-DC converters and low-dropout (LDO) regulators, and a controller to
control the on/off of each power supply and output according to commands from a main system-
on-a-chip (SoC). PMICs specifically designed for smartphone and tablet applications, are constrained
by size limits. Therefore, the power supply ICs integrated in some of these PMICs do not compare
favorably with discrete power supply ICs in terms of performance. The power supplies from a PMIC
might not satisfy system requirements, depending on the loads (ICs and modules) that they serve.
In addition, mobile devices with wireless communication capabilities might generate electromagnetic
interference (EMI) that affects bad impact to not only the communication quality but also internal
power supply circuits. PMICs are generally designed for applications that are not subject to frequent
remodeling. However, smartphones are upgraded frequently to add new features and improve
performance, and each upgrade entails changes to the specifications of internal circuits. It is
therefore impractical to rely on a single PMIC for the power management of all the internal circuits
from the viewpoints of both system design and PMIC design.
In addition, with the global uptake of the LTE wireless standard, many smartphone users now
share photographs and movies on SNS. This is driving substantial improvement in the performance
of smartphone cameras, which have a CMOS image sensor with low power consumption and high
read speed. Generally, it is necessary to supply different voltages to the sensor, core (control) and
I/O sections of a CMOS image sensor. The digital core of a CMOS image sensor that processes data
at high speed tends to consume a lot of power. Nowadays, the digital core is designed to operate at
a very low voltage (around 1 V) to reduce power consumption. In order to accommodate the
decreasing voltage and increasing current consumption, the power supply for the digital core needs
to have excellent AC characteristics, including a high power supply rejection ratio (PSRR) and a fast
load transient response, while providing a high current drive capability. Ultra-small packaging is also
an important factor for space-critical designs like smartphones.
In addition to the V
supply for the output circuit in order to achieve low dropout voltage and thus stable voltage
regulation even at low input voltage. The TCR15AG series provides outstanding PSRR and load
transient response required for CMOS image sensors for smartphone applications. In addition, the TCR15AG series offers 46 LDO regulators with a fixed output voltage from 0.65V to 3.6V to meet a
wide range of application requirements. While providing accurate voltage regulation, all the LDO regulators of the TCR15AG series are available in an ultra-small, thin-profile WCSP package.
input, Toshiba’s LDO regulators of the TCR15AG series have a separate power
IN
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© 2019
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Furthermore, the TCR15AG series has a drive capability of up to 1.5 A and thus meets the current
requirement of CMOS image sensors, and provides overcurrent protection, thermal shutdown, inrush
current limiting, undervoltage lockout, and auto output discharge.
This reference guide uses the TCR15AG (fixed voltage type) LDO regulator as an example to
describe the major features and characteristics of the TCR15AG series. For details of other features and functions of the TCR15AG series, see datasheet.
To download the datasheet for the TCR15AG series →

1.1. Target applications

● Power supply circuits for CMOS image sensors and RF blocks/modules for smartphone
applications
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© 2019
Manufacturer
)

2. Application circuit example and bill of materials

2.1. Application circuit example

Figure 2.1 shows an example of a circuit usi ng the TCR15AG (fixed voltage type) LDO regulator.
V
voltage conditions:
BIAS
V
≦ 1.1V 2.5 to 5.5V
OUT
V
＞1.1V V
OUT
+1.4 to 5.5V
OUT
Figure 2.1 Example of a circuit using the TCR15AG (fixed voltage type) LDO regulator

2.2. Bill of materials

Table 2.1 Bill of materials
No. Ref. Qty Value Part Number
TCR15AG
1 IC1 1 ―
C1
2
(C
1 1.0μF Ceramic, 10V, ±10% ―
BIAS
(fixed voltage
type)
TOSHIBA WCSP6F 1.2 x 0.8
Description Packaging
Typical
Dimensions
mm (inches)
1.0 x 0.5
(0402)
3
4
(C
(C
C2
IN
C3
OUT
1 4.7μF Ceramic, 10V, ±10% ―
)
1 4.7μF Ceramic, 10V, ±10% ―
)
1.6 x 0.8
(0603)
1.6 x 0.8
(0603)
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© 2019

3. Major features of the TCR15AG series

Fabricated using a CMOS process, the LDO regulators of the TCR15AG series feature low current
consumption and small size. With small process geometries, the output de v ice of the TCR15A G series
has low on-resistance and thus a low input-output voltage differential (i.e., dropout voltage). LDO
regulators with a low dropout voltage help reduce the thermal loss and increase the running time of
battery-operated devices.
The TCR15AG series has a bias voltage input (V
) separate from the VIN input, making it possible
BIAS
to reduce dropout voltage to a level lower than that achievable with the conventional CMOS process. Due to this circuit configuration, the TCR15AG series provides much lower dropout voltage than
typical CMOS LDO regulators and thus helps reduce thermal loss. As a result, despite the ultra-small
WCSP package, the TCR15AG series has a current drive capability of 1.5A. Being independent of the
V
input of the LDO regulator, the V
IN
regulation, even in the low input voltage region, without being affected by V
pin helps the TCR15AG series achieves stable voltage
BIAS
. The output voltage
IN
is as low as 0.65V. The following subsections show the unique characteristics of the TCR15AG series
derived from the V
BIAS
pin.
3.1. V
Figure 3.1 shows a conventional LDO regulator. Operating with a power supply from V
regulator drives the gate of an internal P-channel MOSFET with V
Consequently, when V
BIAS
pin
, this LDO
IN
to provide an output voltage.
IN
is low, the MOSFET gate voltage decreases to a level that makes it
IN
impossible for the LDO regulator to maintain a regulated output voltage. Even when a low output
voltage is necessary, a conventional LDO regulator is restricted by the lower limit of input operating
voltage range specified in the datasheet. Therefore, despite the superior low-dropout advantage,
conventional LDO regulators are not well suited for applications requiring a regulated low-voltage
supply. By way of comparison, Figure 3.2 shows the internal configuration of the TCR15AG series, which
drives the gate of an internal MOSFET with a power supply from the VBIAS pin. Being independent
of the VIN input, the VBIAS pin provides several benefits. First, this configuration allows the use of
an N-channel MOSFET. Since it is easier to reduce the on-resistance of the N-channel MOSFET than
that of the P-channel MOSFET, the use of an N-channel MOSFET makes it possible to reduce dropout
voltage. This, in turn, helps reduce power loss and therefore achieve a high-current drive capability.
Second, the LDO regulator can operate at a low input voltage irrespective of VIN and provides a regulated low output voltage with minimum power loss. Next, let’s look at the changes in
characteristics over a range of voltage applied to the VBIAS pin.
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